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Dan Karachio
05-23-2010, 11:34 AM
Hi everyone,

I would really like to buy a Tormek some day, and from reviews I am not interested in the clones, but in the mean time I need to hollow ground quite a few beat up old chisels. I can use stones and/or other methods to put on an edge. Question is, what is a good grinder and what is the best available option for holding a blade to a grinder? As fool proof as possible, because I am not the most steady handed person and I do not have brain cells that tell me when I am at 25 degrees to anything.

I see plenty of slow speed grinders in the 1700 RPM range. Is that slow enough? If not, what do I need?

David Nelson1
05-23-2010, 12:06 PM
Hi Dan,
I have used a Wen wet grinder for years (15+) It's not a great tool, a bit noisy and if your not in a hurry will do a good job holding the angle because it has a guide plate with angles scribed into the end plate. I think mine was 10.00 years ago. I also looking @ getting the Tormac system, but not for chisel primarily but for the planer.

David Weaver
05-23-2010, 12:18 PM
Hi everyone,

I would really like to buy a Tormek some day, and from reviews I am not interested in the clones, but in the mean time I need to hollow ground quite a few beat up old chisels. I can use stones and/or other methods to put on an edge. Question is, what is a good grinder and what is the best available option for holding a blade to a grinder? As fool proof as possible, because I am not the most steady handed person and I do not have brain cells that tell me when I am at 25 degrees to anything.

I see plenty of slow speed grinders in the 1700 RPM range. Is that slow enough? If not, what do I need?

I got a plain old 6" grinder a long time ago to rough things, and bought a 120 grit white wheel. I found out not long after getting into things that the coarse gray wheel on the grinder (the one that costs $6) was far better than the finer white wheel. I think those (finer grit) white wheels are for HSS - they are hard on high carbon steel.

Touch and a clean coarse wheel will keep you from burning steel - you don't need a magic grinder.

Derek Cohen
05-23-2010, 12:19 PM
Hi everyone,

I would really like to buy a Tormek some day, and from reviews I am not interested in the clones, but in the mean time I need to hollow ground quite a few beat up old chisels. I can use stones and/or other methods to put on an edge. Question is, what is a good grinder and what is the best available option for holding a blade to a grinder? As fool proof as possible, because I am not the most steady handed person and I do not have brain cells that tell me when I am at 25 degrees to anything.

I see plenty of slow speed grinders in the 1700 RPM range. Is that slow enough? If not, what do I need?

Hi Dan

Note that a 6" full speed grinder runs at about the same surface speed as a 8" half speed grinder. So you could just get the cheaper option if you are looking for savings.

Next - get a 46 grit 3X Nortons wheel. These are the coolest running wheels around. A cheaper alternative is a 36 or 46 grit white Nortons wheel. Always use a coarse wheel - again cooler running.

Lastly, make sure that you keep the wheels clean. Metal build up creates heat. And a light touch. Take your time.

For rests, the Veritas is helpful as it has a sliding camp for the blade. Another alternative in the Tormek grinder rest, BGM-100.

Regards from Perth

Derek

George Clark
05-23-2010, 12:50 PM
High speed (3600 rpm), low speed (1800 rpm), 8 inch, 6 inch all will work. Technique, a decent tool rest, and a well dressed coarse stone are important. I would refer you to this article by Clark and Williams.

http://www.planemaker.com/articles_grinding.html (http://www.planemaker.com/articles_grinding.html)

Make some wooden templates to set the tool rest to the desired angle. Don't grind all the way the the edge of your chisel. Leave a small flat at the edge of the chisel to finish when you hone them with oil or water stones. Get some steel at the hardware store and practice to develop your technique before you try grinding your chisels.

If you should decide to not use a powered grinder look at Lie-Nielson's website for videos with information on grinding with sandpaper.

http://www.youtube.com/user/LieNielsen#p/u/4/XPDxEb98ah8

George

Don Dorn
05-23-2010, 12:52 PM
I tried different methods but settled on one in an Ian Kirby book. It seems to work great and I haven't overheated a blade yet.

I discovered that I can use the elipse for everything, but it was after I already made the jig in the book that is for 2, 2 3/8 & 2 5/8" plane blades. I added a hole to accomodate a 1 3/4 too, but the elipse works fine on everything. The stop block is the same one I use for setting the sharpening iron - don't ask why it works, I was just very surprised to find that it did.

http://i111.photobucket.com/albums/n124/djdorn/DSCF0003.jpg

http://i111.photobucket.com/albums/n124/djdorn/DSCF0004.jpg

http://i111.photobucket.com/albums/n124/djdorn/DSCF0005-1.jpg

http://i111.photobucket.com/albums/n124/djdorn/DSCF0007-1.jpg

george wilson
05-23-2010, 2:44 PM
36 grit white wheel is miles ahead of the old gray wheels. Most of my younger life I used them when they came into my notice. For over 25 years,i now use blue belts on a belt grinder.

Recently,I got a Jet wet wheel grinder for cheap,new. It quit running soon,as they usually do. I found out that the press on connectors in their little circuit boards often crack,probably during assembly. they are as thin as beer cans,REALLY. I just soldered the wire to the loose connector,and all has been well. If you know this bit of info.,you can use the cheaper Jet just fine,possibly the Grizzly,too.

Russell Sansom
05-24-2010, 4:11 AM
Ron Hock's "the perfect edge" will give you a credible survey of grinding devices.

Brian Ashton
05-24-2010, 10:14 AM
There as many ways to grind as there are to sharpen... so here's some more food for thought to confuse you...

Question I'd have to ask first is:

Do you like to build your own if you can or would you rather buy off the shelf.

If you're the type that likes to DYS and are reasonably handy I'd say build your own slow speed grinder. Personally I'd say they're better and more versatile than any of the commercially available ones. If you're interested I'll post some pics...

Andrew Pitonyak
05-24-2010, 11:32 AM
I would really like to buy a Tormek some day...
I like using sandpaper, but, it is slow. My Worksharp was fine, but, I had trouble not getting a slight skew on the top section... I love my Tormek :)

Jim Belair
05-24-2010, 12:04 PM
If you're the type that likes to DYS and are reasonably handy I'd say build your own slow speed grinder. ..... If you're interested I'll post some pics...

Hi Brian

Yes I'd like to see what you came up with as a shop built slow speed grinder.

Thanks
Jim B

Brian Ashton
05-25-2010, 6:33 AM
It's not pretty but I've attached a few pics of the contraption...

First one was conceived about 27 years ago and was made up of a single phase motor, two 4 step pulleys and a LV tool rest. The lowest speed was around 360rpm. About 8 years ago I mounted a VFD and ditched the 4 step pulleys and made a long tool rest so I could grind 16" planer blades. The rest of the parts haven't changed much.

This thing ranges from 1 to 6500 rpm. True slow speed grinding... or frighteningly high speed that will destroy any wheel in milli seconds.

It uses a plain grey wheel for grinding. At the speeds I grind, 10htz, there's no need for "exotic" wheels that run cooler... Not sure of the rpms as the two pulleys are of different sizes - it's slow though.

Because it's so slow it's very difficult to actually over heat a tool. You'd also think that it would take forever to grind a tool at 10htz but it's actually quicker than on a conventional grinder. The MDF wheel (on the right) and buffing compound makes sharpening stones unnecessary in most situations.

I've tried all sorts of grinding stations and I wouldn't use anything else. Because I can dial it down so much there isn't much I can't grind on it free hand or what ever...

Basic parts:

Mandrel from LV (I like theirs because they have ball bearings)
3 phase motor (any size under 1hp will do)
Variable Frequency Drive (what ever your fancy is. Mine is a Hitachi)
Fan belt
2 pulleys
Grinding wheel (any wheel will do)
Tool rest (I made mine so I could do planer blades)
MDF disk and white compound for buffing
Base